1. How to Round Whole Numbers

2. A Number Line
When rounding number, some times it helps to remember and to use a number line.
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3. Rounding Numbers BASIC RULES
If the number to the RIGHT of the Rounding Number is 5 or more (5, 6, 7 8 or 9) then the LEFT (Rounding Number) number goes UP by ONE place.
2. If the number to the RIGHT of the Rounding Number is 4 or less (4, 3, 2, 1 or 0) then the LEFT (Rounding Number) number remains the SAME.
3. Every number AFTER the Rounding Number becomes 0.
4. Everything BEFORE the Rounding Number remains the same.
5. If the Rounding Number is a 9 and it goes up by one, then a 0 is placed in the Rounding Number Place and 1 is moved to the next place to the LEFT. (same as carrying in adding)

4. How to Round Whole Numbers to the Tens Place
Example: Round 78 to the nearest tens place
| | | | | | | | | | 80 70 78
Use a number line to help you visualize
1. Underline the place you want to round to.
Here we want the tens place

5. How to Round Whole Numbers to the Tens Place
Example: Round 78 to the nearest tens place
2. Look to the right of the place you want to round to,
Now look to the right of the 78
tens place
Look here
If the digit is 5, 6, 7, 8 or 9 – the digit in the tens place goes UP by 1
If the digit is 0, 1, 2, 3 or 4 – the digit in the tens place STAYS THE SAME
The 7 in the tens place
goes up by 1 to 8

6. How to Round Whole Numbers to the Tens Place
Example: Round 78 to the nearest tens place
3. Next, the digits to the right of the rounding place become zero.
Now the 8 becomes zero becomes
4. Anything to the left of the rounding place remains the same.
So 78 rounded to the nearest tens place is 80

7. How to Round Whole Numbers to the Tens Place
Example: Round 123 to the nearest tens place
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130
120
123
To Round: Here is the tens place
Look to the right , so the 2 in the tens
place stays the same.
On the left On the left hand side, all
stays the same
 123 rounds to 120

8. How to Round Whole Numbers to the Tens Place
Example: Round to the nearest tens place
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1100
1090
1099
To Round:
Here is the tens place with 9 to its right
The 9 in the tens place goes up by one.
**But, 9 goes to 10 and we only have one place
So we need to move over one more place to the
left adding 1 to the hundreds place and 0 to the
tens place. All on right changes to zero.
 rounds to 1 100

9. How to Round Whole Numbers to the Tens Place
Example: Round the following to the nearest tens place
To Round: 2 65
234
2 343
45 678
65 723
__2 65
234
2 343
45 678
65 723 70
230
2 340
45 680
65 720
Look to the value of the place to the right of the tens place

10. Practice Round the following numbers to the nearest tens place. 45 67
123
456
890
1232
a) 50
b) 70
c) 120
d) 460
e) 890
f) 1 230

11. How to Round Whole Numbers to the Hundreds Place
Example: Round 145 to the nearest hundreds place
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200
100
145
Use a number line to help you visualize
1. Underline the place you want to round to.
Here we want the hundreds place

12. How to Round Whole Numbers to the Hundreds Place
Example: Round 145 to the nearest hundreds place
2. Look to the right of the place you want to round to,
Now look to the right of the 145
tens place
If the digit is 5, 6, 7, 8 or 9 – the digit in the hundreds place goes UP by 1
If the digit is 0, 1, 2, 3 or 4 – the digit in the hundreds place STAYS THE SAME
The 1 in the hundreds place
stays the same

13. How to Round Whole Numbers to the Hundreds Place
Example: Round 145 to the nearest hundreds place
3. Next, the digits to the right of the rounding place become zero.
Now the 4 and 5 becomes zero becomes
4. Anything to the left of the rounding place remains the same.
So 145 rounded to the nearest hundreds place is 100

14. How to Round Whole Numbers to the Hundreds Place
Example: Round the following to the nearest hundreds place
To Round: 2 65
234
2 343
45 678
65 723
_ _ 2
_65
234
2 343
45 678
65 723
100
200
2 300
45 700
65 700
Look to the value of the place to the right of the hundreds place

15. Practice Round the following numbers to the nearest hundreds place. 49
136
293
456
1 890
12 345
a) 0
b) 100
c) 300
d) 500
e) 1 900 f)

16. How to Round Whole Numbers to the Thousands Place
Example: Round to the nearest thousands place
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10 000
9000
9 871
Use a number line to help you visualize
1. Underline the place you want to round to.
Here we want the thousands

17. How to Round Whole Numbers to the Thousands Place
Example: Round to the nearest thousands place
2. Look to the right of the place you want to round to,
Now look to the right of the
thousands place
If the digit is 5, 6, 7, 8 or 9 – the digit in the thousands place goes UP by 1
If the digit is 0, 1, 2, 3 or 4 – the digit in the thousands place STAYS THE SAME
The 9 in the thousands place
goes up by 1

18. How to Round Whole Numbers to the Thousands Place
Example: Round to the nearest thousands place
3. Next, the digits to the right of the rounding place become zero.
Now the 8,7 and 1 becomes zero becomes
4. Anything to the left of the rounding place remains the same.
So rounded to the nearest thousand place is

19. How to Round Whole Numbers to the Thousands Place
Example: Round the following to the nearest thousands place
To Round: 2 65
234
2 343
45 678
65 723
_ _ _ 2
_ _65
_234
2 343
45 678
65 723
2 000
46 000
66 000
Look to the value of the place to the right of the thousands place

20. Practice Round the following numbers to the nearest thousands place.
1 234
78 902
12 666
9 987
2 890
a) 1 000 b) c) d)
e) 3 000 f)

21. How to Round Whole Numbers to the Ten Thousands Place
Example: Round to the nearest ten thousands place
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20 000
19 000
19 012
Use a number line to help you visualize
1. Underline the place you want to round to.
Here we want the ten thousands place

22. How to Round Whole Numbers to the Ten Thousands Place
Example: Round to the nearest ten thousands place
2. Look to the right of the place you want to round to,
Now look to the right of the
ten thousands place
If the digit is 5, 6, 7, 8 or 9 – the digit in the ten thousands place goes UP by 1
If the digit is 0, 1, 2, 3 or 4 – the digit in the ten thousands place STAYS THE SAME
The 1 in the ten thousands place
goes up by one

23. How to Round Whole Numbers to the Ten Thousands Place
Example: Round to the nearest ten thousands place
3. Next, the digits to the right of the rounding place become zero.
All the numbers on the becomes
right becomes zero
4. Anything to the left of the rounding place remains the same.
So rounded to the nearest ten thousands
place is

24. How to Round Whole Numbers to the Ten Thousands Place
Example: Round the following to the nearest ten thousands place
To Round: 2 65
234
2 343
45 678
65 723
_ _ 2
_65
234
2 343
45 678
65 723 70
230
2 340
45 680
65 720
Look to the value of the place to the right of the tens place

25. Round the following numbers to the nearest ten thousands place.
Practice
Round the following numbers to the nearest ten thousands place.
45 653 a) b) c) d) e)

26. How to Round Whole Numbers to the Hundred Thousands Place
Example: Round 145 to the nearest hundreds place
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200
100
145
Use a number line to help you visualize
1. Underline the place you want to round to.
Here we want the hundreds place

27. How to Round Whole Numbers to the Hundred Thousands Place
Example: Round 145 to the nearest hundreds place
2. Look to the right of the place you want to round to,
Now look to the right of the 145
tens place
If the digit is 5, 6, 7, 8 or 9 – the digit in the hundreds place goes UP by 1
If the digit is 0, 1, 2, 3 or 4 – the digit in the hundreds place STAYS THE SAME
The 1 in the hundreds place
stays the same

28. How to Round Whole Numbers to the Hundred Thousands Place
Example: Round 145 to the nearest hundreds place
3. Next, the digits to the right of the rounding place become zero.
Now the 4 and 5 becomes zero becomes
4. Anything to the left of the rounding place remains the same.
So 145 rounded to the nearest hundreds place is 100

29. How to Round Whole Numbers to the Hundred Thousands Place
Example: Round the following to the nearest hundred thousands place
To Round: 2 65
234
2 343
45 678
65 723
_ _ 2
_65
234
2 343
45 678
65 723 70
230
2 340
45 680
65 720
Look to the value of the place to the right of the tens place

30. Round the following numbers to the nearest hundred thousands place.
Practice
Round the following numbers to the nearest hundred thousands place. a) b) c) d) e)

31. How to Round Whole Numbers to the Millions Place
Example: Round 145 to the nearest hundreds place
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200
100
145
Use a number line to help you visualize
1. Underline the place you want to round to.
Here we want the hundreds place

32. How to Round Whole Numbers to the Millions Place
Example: Round 145 to the nearest hundreds place
2. Look to the right of the place you want to round to,
Now look to the right of the 145
tens place
If the digit is 5, 6, 7, 8 or 9 – the digit in the hundreds place goes UP by 1
If the digit is 0, 1, 2, 3 or 4 – the digit in the hundreds place STAYS THE SAME
The 1 in the hundreds place
stays the same

33. How to Round Whole Numbers to the Millions Place
Example: Round 145 to the nearest hundreds place
3. Next, the digits to the right of the rounding place become zero.
Now the 4 and 5 becomes zero becomes
4. Anything to the left of the rounding place remains the same.
So 145 rounded to the nearest hundreds place is 100

34. How to Round Whole Numbers to the Millions Place
Example: Round the following to the nearest millions place
To Round: 2 65
234
2 343
45 678
65 723
_ _ 2
_65
234
2 343
45 678
65 723 70
230
2 340
45 680
65 720
Look to the value of the place to the right of the tens place

35. Round the following numbers to the nearest millions place.
Practice
Round the following numbers to the nearest millions place. a) b) c) d) e)

36. How to Round Whole Numbers
Example: Round 78 to the nearest tens place
| | | | | | | | | | | | 80 70 78
Use a number line to help you visualize
1. Underline the place you want to round to.
Here we want the tens place

37. Some Examples: 1. Round to the nearest 10 12 ____________
12 ____________
Or use a number line is 12 closer to 10 or to 20?

38. Examples
Because ...
rounded to hundredths is 3.14
... the next digit (1) is less than 5
rounded to tenths is 1.3
... the next digit (6) is 5 or more
rounded to 3 decimal places is 1.264
... the next digit (5) is 5 or more
134.9 rounded to tens is 130
... the next digit (4) is less than 5
12,690 rounded to thousands is 13,000
1.239 rounded to units is 1
... the next digit (2) is less than 5